Compilare: main.cpp: In function 'bool cuplaj(int, int)': main.cpp:81:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a.size(); ++i) { ~~^~~~~~~~~~ main.cpp:83:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < b.size(); ++j) { ~~^~~~~~~~~~ main.cpp:93:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= a.size(); ++i) { ~~^~~~~~~~~~~